U.N. Deputy Secretary General Asha-Rose Migiro as well as conservationists Bindi and Terri Irwin pose with an ice sculpture of a polar bear at U.N. headquarters Tuesday during World Environment Day. Melting in 80 degree heat, the sculpture was a symbol of global warming's impact.

UNITED NATIONS — The U.N.'s celebration of World Environment Day on Tuesday featured a melting polar bear, youngsters dancing with cardboard fish, children painting shoes to symbolize carbon footprints, and an appeal from the daughter of late wildlife expert Steve Irwin to skateboard or take public transportation to school.

Dozens of students gathered in the outdoor plaza at U.N. headquarters to hear Bindi Irwin, the 8-year-old star of a new wildlife show to air on the Discovery Kids Channel in the United States and on the Australian Broadcasting Corp., read a children's book on this year's theme: "Melting Ice: A Hot Topic?"

"We really do have to save our oceans," said Irwin, whose father, the late Australian "Crocodile Hunter," was killed by a stingray last fall while filming one of his popular television documentaries.

Her biggest message to kids around the world was "Don't buy wildlife products." She also encouraged people to take public transportation, skateboard, bike ride or walk to school and work "to help the ozone layer," she said.

As she spoke, a polar bear ice sculpture behind her melted in the 80 degree heat — a visual representation of the effects of global warming on animals and their habitats.

NBA star and footprintsNew York Knicks basketball player Stephon Marbury donated 1,000 shoes from his footwear line "Starbury" to a global campaign to get children and adults to focus on reducing their carbon footprints — the amount of carbon dioxide released by a single household or individual. Carbon dioxide contributes to global warming.

The project, Art Miles Shoes of Hope, has recruited over 600 students in New York City schools to paint shoes. They will be sent to children in developing countries along with notes on the students' hopes to prevent climate change.

The painted shoes were placed along an artwork called "Uniting Painting" by artist and cartoonist Ranan Lurie, that runs from inside the U.N. building to New York's East River, and to Roosevelt Island. There are also panels in countries around the world.

Lurie said the artwork provides a physical link between people on different continents "to create a common denominator, especially now that we have to unite around the subject of global warming."

Margaret Chan, the World Health Organization director-general, estimated that 60,000 people die every year — mostly in the developing world — because of climate-related natural disasters.

"Limiting the impact of climate change is about saving lives and livelihoods, as much as it is about protecting the natural environment," she said in a statement.

Aiming at youngstersThe day's focus was clearly on getting that message to youth.

"We're all concerned about climate change, but most kids don't know what to do," said Edwin Gragert, executive director of the International Education and Resource Network, which is part of a project launched Tuesday to get young people to help spread the message on climate change on the Internet.

The project, called "(OF)2: Our Footprints, Our Future," aims to get 1 million students to measure their carbon footprint and to develop strategies for reducing personal carbon usage.

"We want to give them the tools so that they change the lifestyles of our population," Gragert said.

Thirty fifth-graders from PS 124 in New York's Chinatown neighborhood put together a performance for World Environment Day that addressed the plight of fish in the affected oceans.

They held cardboard painted fish, danced through each other, and read messages gathered over the Internet from young people talking about environmental effects on fish by their homes in the Philippines and Malaysia.

"There is always hope. Hope in the future, hope in the next generation," Juanita Castano, director of the U.N. Environment Program's New York office, told Tuesday's U.N. commemoration.

World Environment Day was established in 1972 by the U.N. General Assembly to raise worldwide awareness about the environment.

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